I honestly wouldn't worry about it right now (particularly if you're bf'ing), but if you really are concerned, then doing a little bit of snack prepping each day, so you've got healthy stuff to hand that's as easy to grab as a biscuit is will help.
Make some crudites, have a pot of hummus ready to go, maybe some sliced up pitta bread if you want carbs, make a fruit salad you can just serve some of when you fancy it. When I was dieting, I used to freeze Muller Light yogurts into 3 portions each (I guess you could use ice cube trays or Tupperware) and it's quite like ice-cream (although it's high in sugar, but sometimes you need the sugar!) and I'd chop Mars Bars into 5, wrap each piece in cling film and keep in the fridge - when they're like that each one lasts ages. Air popped popcorn and rice cakes are always handy too, along with nuts as @YouCantBeSadHoldingACupcake has suggested above. Basically it's about having stuff handy when you need it.
My diet after I had each of my DDs was pretty terrible to be honest (hence the actual dieting that had to take place afterwards - it took 3 years, but I've lost 10 stone since I had my youngest and she's just turned 10, so I've kept it off for 7 years now). Before I went to bed, I would set up my 'feeding station' on the sofa, ready for the night feeds (DH was up at 6am for work and DD1 was 20 months and asleep in the only other bedroom, so I would take DD2 out of her Moses basket in our room and head downstairs for nighttime feeding). It consisted of: feeding pillow, muslins, spare nappies, sacks and wipes, TV remote control, a big bottle of water, a packet of chocolate digestives, a bar of Dairy Milk and a packet of custard creams... oh, and an apple!
Congratulations on your new baby!